1. Field of the Invention
The present invention results from the work carried out at l'Institut Francais du Petrole by Mesdames Francoise BEHAR and Jeannine ROUCACHE and at the DELSI Instruments firm by Messrs. Jean AUGER and Luc BOUDET.
This invention relates to a device usable for heating, and more particularly for the pyrolysis, of solid or liquid samples taken in small amounts.
The device of the invention is particularly suitable for carrying out the follow-up pyrolysis of the chromatographic analysis of pure organic materials (asphaltene kerogen, coal), or materials dispersed in a mineral matrix (recent sediments, source rocks), for example for establishing a relationship between the composition of the hydrocarbon fraction of a crude oil and its asphaltene pyrolysat, for establishing a correlation between the kerogen pyrolysats and the asphaltenes extracted from the same source rock, or else for knowing the modification of these pyrolysats with the geological evolution (depending on the depth in the same formation); these techniques being possibly used for effecting correlations between the crude oil and the source rock and correlations between crude oils.
The applications given above are however given solely by way of examples and must not therefore be considered as limiting the field of application of the device of the invention.
2. Description of the Prior Art
Devices are already known usable for the prolysis of samples taken in small amounts, these devices comprising a tubular liner inside which is defined a zone for heating the sample, heating means and means for measuring the temperature in said zone, a sample holder adapted to be introduced into the tubular liner as far as the heating zone. The tubular liner has an effluent outlet orifice which is connected to measurement and analysis apparatus. These devices comprise an orifice for introducing a vector gas for displacing these effluents, the orifices being situated on each side of said heating zone.
The sample holder is associated with a rod which is engaged in the tubular liner.
The main disadvantage of some of these prior devices is that the sample subjected to pyrolysis is situated in a confined space. This confined space is formed for example by a crucible having a cover, which does not allow complete scavenging of the sample by the vector gas.
Another disadvantage of the prior devices is that they have a relatively large useless volume between the pyrolysis oven and the trap where the pyrolysis products are retained or the measuring or/and analysis apparatus to which the oven is connected.